Taper-boring bar.



P. W. CURTIS.

TAPER BORING BAR.

A'PPLIUATION TILED JUNE 7, 1913. l fi l gli Patented Mar. 31, 1914,

2 SHEETS-SHEET 1.

' H M l 25.

F. W. CURTIS.

TAPBR BORING BAR.

APPLICATION FILED JUNE 7, 1913.

1 91 91 Patented Mar.31,1914.

2 SHEETS-SHEET 2.

FRANK w. cun'rrs, on DENVER, cononano.

PAPER-BORING BAR;

aoenem.

Specification of Letters Patent.

Patented Mar. 31, 1914:.

Application filed June 7, 1913. Serial No. 772,307.

To all whom it may concern: 7

Be it known that l, FRANK W. CURTIS, a

citizen of the United States, residing in the city and county of Denverand State of Colorado, have invented certain new and useful Improvementsin Taper-Boring Bars; and'I do declare the following to be a full,clear, and exact description of the invention, such art to which itappertains to make and use the same, reference being had to theaccompanying drawings, and to the letters and figures of referencemarked thereon, which form a part of this specification.

My invention relates to improvements in tools adapted for use in boringor forming taper holes, and includes a radially movable bar, in which isjournaled a feed screw carrying a nut,v in which the boring tool ismounted, the radial bar, screw and tool being adjustable according tothe cline required for the wall of the hole. Provision-is also made forautomatically actuating the feed screw during the reamingoperation. Itmay be assumed that originally the hole acted upon by this tool iscylindrical, the object of my present improvement being by reaming orcutting out the hole to give its wall the desiredinclme ortaper,resulting from a correspondingly lncllned position given to theradialbar upon which the tool is mounted, whereby a comparatively deepcut or bite is taken by the 'tool at one end of the hole, the said outor bite gradually diminishing in degree toward the opposite end of thehole.

Any suitable means may be employed for imparting the rotary movement tomy improved device. As illustrated in the drawing, the device isconnected with a horizontally disposed chuck carried by a stationarycolumn, the chuck being provided with a rotary member connected inoperative relation with my improved device, the rotary movement of thesaid chuck member being imparted through the instrumentality of shaftsand gears suitably arranged for the purose.

Having briefly outlined my improved construction, I will proceed todescribe same in detail, reference being made to the accompanyingdrawing, in which is illustrated an embodiment thereof. Y

In this drawing-Figure 1'is .an elevation, partly in section, showing myimproveas will enable others skilled in the taper or l11' ment connectedin operative relation and in posit on for use. Fig. 2 illustrates thedeylce in detail, and on a larger scale. Fig. 3 1s a top "plan view ofthe device or a View looking in the direction of arrow 3, Fig. 2.

Fig. 4 is a section taken on the line 44, I

Fig. 2, looking downwardly. Fig. 5 is a section taken on the line 55,Fig. 2, looking toward the right. i

The same reference characters indicate the same parts in all the views.

Let the numeral 5 designate a vertically disposed frame member, whoseupper portion is provided with a pair of clamping 'jaws 6, spaced toreceive the upper extremity of a bar 7, pivoted, as shown at 8, to havea radlal movement in a socket 9 formed in a horizontal projection 10, atthe bottom of the frame member 5. The lower extremity of this framemember is equipped with .a cone-shaped member 12, adapted to engage astationary part 13, when the device is in use, while the upper extremity14 of the frame member is adapted to enter a socket 15, formed intherotary member 16 of a chuck 17, carried by a horizontal arm 18,vertically movable on a stationary column 19, and adjustable thereon forsuch vertical movement through the instrumentality of a feed screw {1,engaging a nut formed in the arm adjacent the column, the said feedscrew 4: being j ournaled at the top and bottom in bearings 20 and 21,or in any other sutiable manner. The rotary member 15 of the chuckcarries. a gear 22, meshing with a gear23 fast on ahorizontally-disposed shaft 24, journaled in the arm 17 and carrying atits opposite extremity a gear 25, meshing with a similar gear 26 mountedon the-upper extremity of a shaft 27, whose lower extremity is providedwith a gear 28 meshing with a similar gear 29 fast on a shaft 30,carrying an exposed operating wheel 31. The construction just describedand illustrated in Fig. 1 of the drawing, is one suitable means foroperating the rotary member of a chuck for imparting the rotary movementto my improved device for reaming out a hole to give its wall a suitabletaper or inclination, as heretofore explained.

The pivoted bar 7 has one of its longitudinal edges of dove-tailedshape,as shown at .32, to engage a socket 33 of counterpart ing pivoted atits'lower extremity, as shown at 36, and journaled at its'upperextremity in the horizontally-disposed part 33 of the bar 7, the saidpart 33 passing between the clamping jaws 6 of the frame member 5, theupper extremity of the bar 7 and its connections being held in thedesired position of adjustment between the said jaws by means of a bolt37 passing through registering openings formed in the said jaws andbeing secured by a nut 38. The outer extremity of the part 33of the bar7 extends upwardly beyond the clamping jaws 6, as

7 shown at 39, and merges into a bearing 40,

in which is journaled a short shaft 41, having a gear 42 at oneextremity, the'said gear meshing in a similar gear 43, fast on the upperextremity of the feed screw 35. The extremity of the shaft 41 oppositethe gear 42 is equipped with a star wheel 44, which is made fast thereonby means of a set screw 45, or in any other suitable manner. virtue ofthis construction, provision is made for imparting intermittent rotarymovement to the feed screw during the reaming operation of the cuttingtool 46, which is clamped to one side of the nut 34, by means of a plate47, the latter being held in place by means of a cap screw 48, passedthrough registering openings formedin the plate 47 and the tool 46, thescrew entering a threaded socket formed inthe nut. An auxiliary fillerplate 49 is also interposed between the plate 47 and the nut, above thetool 46, in

' order to maintain the clamping plate parallel with the adjacent wallof the nut.

Suspended from the horizontal arm 18 is a vertically adjustable member50, which is secured to the said arm by a set bolt 51, passing through aslot 52 formed in the member 50 and threaded into the arm 18. The lowerextremity 53 of this member 50 occupies a position in the path of theprojections 54 of the star-wheel 44, whereby, as theframe member 5 andits connections are rotated during the reaming operation, the member 50will engage the star-wheel during each revolutionofthe structure andimpart a partial rotation to the feed screw 35, by virtue of theshaft-and-gearingconmotion between the star-wheel and the screw, asheretofore explained.

'From the foregoing description, the use and operation of my boring barconstruction will be readily understood. It may be assumed that the part55 containing an opening 56 is suitably supported on separated members57 held in place by bolts 58, whose heads enter a groove 59 formed inthe stationary base 66 upon which the column 19 is mounted. The lowerportion of the framework of my improved device is passed through theopening 56 and its cone-shaped member 12 is caused to engage astationary plate 13, or any other suitable support. The

upper extremity 14 of the device is inserted in the socket 15 of therotary member 16 of the chuck. The upper extremity of the bar 7 is thenadjusted between the jaws 6 to give the bar 7 and its attachments thenecessary inclination according tothe degree of taper which is to begiven the wall of the openmg 56 upon which the tool is to act. The toolis then rotated by imparting rotary -movement to the part 16 of thechuck a feed screw 35, as heretofore explained.

' In order tomanually rotate the feed screw 35 for the purpose ofquickly moving the same upon the screw from its lowermost to an upperposition, a removable crank 61 may be employed, the said crank having asocket to receive the squared extremity 60 of the shaft 41, the'saidextremity extending beyond the star-wheel for the purpose.

' Oneof the jaws 6 may be graduated as a guide during the adjustment ofthe bar 7 to give the latter the desired inclination, in

order to insure accuracy in the degree of adjustment, and to facilitatethis operation the upper part 39 of the bar 7 is equipped with aprojection 62, which extends above the graduated part of the jaw.

I claim v 1. The combination of a frame member rotatably mounted, a barpivoted thereon and arranged to occupy a position inclined to the axisof the frame member, a feed screw having one extremity journaled in saidbar and its opposite extremity in the frame member and whose axis isparallel with the bar, a nut slidable longitudinally on the bar andhaving a threaded connection with the feed screw, a cutting tool carriedby the nut, means for rotating the frame member and its connections onthe axis of the frame member, and independent means for rotating thefeed screw on its own axis.

2. The combination of aframe member rotatably mounted and havinglaterally projecting clamping jaws, a bar pivoted on the frame member atone extremity, its opposite extremity passing through the jaws andadjustabletherein to cause it to occupy positions of varyinginclination'to the axis of the framemember, a feed screw pivoted on theframe member at one extremity, its 0p posite extremity being journaledin the adjacent part of the bar which is bent. ap-

1ion, a nut slidable on the bar and threaded on the screw, means forimparting rotary.

movement to the frame member and means i 101' simultaneously impartingintermittent rotary movement to the screw on its own axis.

3. The combination of a frame member rotatably mounted, a bar pivoted atone extremityon the said member and adjustable to occupy positions ofvarying inclination to the axis of the frame member, the'latter havinglaterally projecting jaws between which the bar is locked in the desiredposition of adjustment, a screw pivoted on the frame member at oneextremity and journaled in the bar at its opposite extremity to maintainits axis parallel with the body of the bar, a nut slidable on the barand threaded on the screw, a shaft journaled in the bar and havingastar-wheel, an operative connection between the shaft and screw forrotating the latter, means for rotating the frame member, and astationary part arranged in the path of the star-wheel to impart rotarymovement to the latter and to the screw on its own axis during therotation of the frame member on its axis.

4. The combination of a frame member rotatably mounted, a bar pivoted atone extremity of said member and adjustable to occupy positions ofvarying inclination, to the axis of the frame member, the latter havinglaterally projecting jaws between which the bar is locked in the desiredposition of adjustment, a screw pivoted on the frame member at oneextremity and journaled in the bar at its opposite extremity to qmaintain its axis parallel with the body of the bar, a nut slidable uponthe bar and threaded by the screw, means for imparting rotary movementto the frame member, and

means for simultaneously imparting intermittent rotary movement to thescrew on its own axis.

In testimony whereof I aflix my signature in presence of two witnesses.

FRANK W. CURTIS.

Witnesses:

A. J. OBRIEN, E. M. WAUDBY.

